Switchboard call-signal apparatus and circuits



R. W. MORRIS.

SWITCHBOARD CALL SIGNAL APPARATUS AND CIRCUITS.

APPLICATION FILED MAR. 15. I919.

1,427,695. Patented Aug. 29, 1922.

2 SHEETS-SHEET I.

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SWITCHBOARD CALL SIGNAL APPARATUS AND CIRCUITS. APPLICATION men MAR. 15. 1919.

1,427,695 PafentedAug. 29, 1922.

2 ISHEETSSHEET 2.

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A TTO'RNEY llhll'l'El) STATlilfi PATENT OFFlfiE.

ROBERT w. re rints, or nosLYn. new YORK, Assrcnon TO AMERICAN TELEPHONE AND TELEGRAPH COMPANY, A CORPORATION or new YonK.

This invention relates to switchboard call.

signal apparatus and circuits, and particularly to arrangements for facilitating the answering of incoming calls.

Subscribers lines and other types of line circuits at the present time are commonly provided, not only with a single answering lamp and answeringjack, but with addi tional lamps and jacks at other positions of the switchboard. All the lamps for any line are connected in multiple and consequently they respond simultaneously to an incoming call. Naturally, several opera.- tors often attempt to answer the same call, and in doing so not only perform unnecessary work, but create a certain amount of confusion and delay.

By the present invention these answering lamps are so arranged that under ordinary circumstances a call is indicated only by the main or primary answering lamp. In case the operator for this position of the switchboard is busy or not at her position, the call is indicated by a secondary lamp, unless also the operator for the secondary lamp is busy or not at her position, in which case the signal is given by a tertiary answering lamp. In case the operators at all three positions are busy, the signal is given in one arrangement at any desired position as, for example, by the primary answering: lamp. In another arrangement the signal is given simultaneously by all three answering lamps. In the first case the primary answering lamp is extinguished and one of the other lamps is lit it the operator at one of the other answering lamps is first to become free. In tl e second arrangementthe signal disappears at two of the positions as soon as the operator at the remaining position becomes free.

The above and other objects and advantages of this invention are attained as'described below, reference be had to the ac companyingg drawings, in which Figure 1 is a diagrammatic view showing circuits cmbodying the invention applied to three po- Specification of Letters Patent. Patented A 0 29 1922 Application filed March 1.5, 1919.

Serial No. 282,831.

sitio ns of a multiple switchboard. Fig, 2 is diagrammatic view showing a mo difica tioncf the circuit arrangements of Fig. 1. Slmilar reference characters refer to similar parts in each of the views.

J In 1, the positions I, II and III of the switchboard are equipped with apparatus of the following description:

E E and E, are line relays which are responsive to subsculoers or other line circuits of the usual type. In practice there are a plurality of line relays associated with each position of the board, but for the present description only one relay is shown for each position for the sake of simplicity.

In front of the board are mounted answering lamps for indicating calls coming; 111 on the line circuits. .There are three types of lamps: primary, A,, A, and A secondary, B,, B and B and tertiary, 6,, C and C These lamps have been shown in a horizontal row for clearness, but it is understood that in practice each position is provided with a bank of each kind of lamp, the primary lamps being located in the lower partof the panel in order to be most convenient to the operator, the secondary lamps being placed above the primary ones, and the tertiary lamps being placed above the secondary lamps.

Auxiliary signal lamps 1),, D and D of larger candle power than the answering lamps are placed at each position directly in front of the operator. These lamps are provided to draw the operators attention to a call indicated by any one of the answering lamps at the corresponding position. They are for this purpose controlled by auxiliary signal relays H K, L H K L and H K, and L the windings of which are in series with the answering lamps, as shown in the drawing and explained hereinafter.

The switchboard is further provided with relays G G and G, which control the cir cuits of the answering lamps in the manner explained below. These relays are in turn governed by contacts 6, 7 and 8. contacts 6 being controlled by the relays N N and N, of the operators telephone sets, contacts 7 being operated by the listening keys, and contacts 8 being actuated by the call circuit keys.

The control of the above apparatus is effected by the following circuits:

Line relay E is controlled by a line cir though closed at relay G cuit of the usual type, which, not forming part oi the present invention, has not been shown in order to avoid unnecessary complexity of the drawing. For the present purpose it is necessary only to note that relay E, is energized and its contacts closed when the subscriber removes his receiver fromthe hook to initiate a call. It is llDClGT- stood that the line circuit tor relay E, is provided with the usual answer'iiig' iaclrs, one at each position l, U, Ill. These jacks have also l omitted from the drawing. tl ormin r no part of the present invention.

Three answering); lamps, namely primary lamp L2,, secondary lamp 827 and tertiary lamp l are responsive to line relay E and in the ura*-.vin,ethe circuits for these lamps and the circuits associated therewith are shown in heavy lines so that they may be easily traced.

The circuit for primary lamp A, is: from battery ll,, through bacl: contact of relay G wire 5, relay l-l lamp it, and contact of line relay E through ground back to battery F The circuit- :tor secondary lamp is: from battery F through front contact at of relay G wire 10, back contact 11 of rela 5%,, wire 12, relay K wire 13, lamp 13,, wire lot and contact of line relay E, through ,c'round back to battery F The circuit for tertiary lamp C, is the same that of lamp B, up to and including wire 10, then through front cont-act- 11 ot relay G wire 21, back contact 16 ot rcla G wire 17, relay T1,, wire 18, lamp C wire 15 and contact of line relay E, through ground back to battery ll.

The circuits for the answering; lamps responsive to the other line relays are similar and need therefore not be separately described.

It will be noted that while the circuits of all three lamps A ll, and C, are governed by contacts of line relay E they are so controlled by relays (l (l and G, that only one lamp at a time responsive to relay E,. is SllOWl'l in the drawing", relays G G and "3 are normally uuenergized. The circult primary lamp A, includes a back contact oi? relay G, and is therefore normally closed. The circuit for secondary lamp B includes a front contact of relay G and a back contact of relay G, so that this circuit is normally open at relay G though closed at relay G The circuit tor tertiary lamp includes trout contacts on relays G, and t and a back contact on relay G so that this circuit is normally open at relays G, and G As long as relay G, is not energized lamp A, alone is responsive to relay E the circuits of the other lamps beingopen at relay G When relay G, is energized, lamp A, ceases to be responsive to relay E its circuit being open 7 it is rendered resaonsive to relay i l in all three r lays i G and G, are energized. This circ it extends from battery F through the front contact 1 of rela i 3,, wire l0, trout contact i l of relay 5%,, wire 21, front contact 16 of rel ay (1 wires 19 and 5, relay ll lamp Br, and contact 01'? relay E, through ground back to battery l .lt will be noted that in this circuit the connection 19 completes a shunt around back contact l of relay G,, which connection is complete, however, only in case all three relays G G and G, are energized, and is lJIOlIeI'l soon as one of these relays is rte-energized.

The relays G G and C as stated above, are norn' lly uuere ized l each of these relays is so controlled t. it is energized only in case the operator at "he corresponding position is busy or when there is no operator at the position. hihus relay G, is controlled by circuit trom battery F thrmigh the winding of relay G wire 25 and contacts 6, 'i" and 8 in parallel, so that the relay is energized when any one of these contacts is dosed. Normally each one of these contacts is open, contact 6 being a back -.ontact on the relay ll, oi the operators telephone set and closed only when the operator is not at her p sition; and contacts '7 and 8 being on the ()l)Glfl.i;Ol"S listening and call circuit key respectively, and closed when she is tallcnp; to subscriber or another operator. lt is to be understood, hovvev that the above arrangement oi? contacts tor the control ct (l, is merely illustrative. and Jill where desired some of these contacts may be omitted and other contacts or their eipiivalents added to meet the requirements peculiar to the circumstances under which this invention is to be used.

it should here he noted that hereinafter a position of the switchboard is described as bus f when the operator is en gagged with a previous call. or other duty, or when there is no open-.qtor at the position, and tree when. the operator at her position awaiting a call. l n similar manner relays G and G, are controlled to close their contacts on y if their respective positions are busy.

As stated hereinbetore, an auxiliary signal relay is connected in series with each group of answering lamps, thus on position I relays K H and L are in series with lamps 13,, A and C The contacts 36, 37 and 38 of these relays are connected in parallel in the circuit of the auxiliary signal lamp 1),, so that current flows through this lamp from battery P, when any one of these contacts is closed. In. this manner lamp D is caused to respond to every signal lamp on the corresponding panel and serves to draw the operators attention to every call indicated on this panel. Lamps D and'D are cont-rolled in like manner lVith the above description of the ap paratus and circuits in mind, a better un-- derstanding of the invention may be had troma description of the operation thereof.

Normally, relay G, is unergized because contacts 6, 7 and 8 are open, as stated here inbefore. When, therefore, a call comes in on line relay E it is indicated by primary lamp A, but not by the secondary and tertiary lamps B, and C Thus the signal is given only to the operator at position I and she proceeds to answer the same by plugging in at the primary answering jack.

In case position I is busy and position ill is free, relay G is energized and relay G is not energized. As explained hereinbettore the secondary lamp B is now responsive to relay E, so that it alone responds to a call on the line, the primary and tertiary lamps remaining dark. The operator at position 11, not being busy, may proceed. at once to answer the call by plugging in at the corre sponding multiple answering jack at her position.

If, however, position II is busy, as well as position 1, position III alone being free, relays G and G are energized but relay G, is not energized. Consequently tertiary lamp C, is responsive to line relay E, and a call coming in on this relay is indicated by the tertiary lamp, but not by the primary and secondary lamps. In this case then, the operator at position H1 is notilied ot the call and she proceeds to answer the same by plugging in at the multiple answering jac'lr at her position.

Finally, if positions I, 11 and HI are busy simultaneously the above described auxiliary circuit of lamp A, is closed by relays G G and G, so that lamp A, responds to a call coming in on relay E and the open ator at position I may answer the call as soon as she is freeto do so. If in the meantime either of the other positions 11 or Ill. becomes free, the signal disappears at busy position I because the circuit of the primary lamp A, is broken by the release oi. relay G or and the circuit of the secondary or tertiary lamp is closed, as the case may be. Thus, i1 all three positions are busy when the call comes in, the signal is temporarily given by the primary lamp, but immediately transferred to one of the other positions ii": the operator therea't is first to become tree.

This feature of the invention is of prime importance in eiiecting a speedy response to calls.

The operation of the other answering lamps of the switchboard in response to calls coming in on the other line relays is similar and needs therefore no separate description. The modification or the invention shown in Fig. 3.0 difiers from the arrangements described in Fig. 1, in that relays M M and M, are added to the apparatus for the positions. The winding of relay M, has one end connected to ground and the oth r end connected to the front contact 16 or the adjacent relay G so that relay M is energized by current from battery F when relays G G and G, are closed, i. e., when positions I, II and Ill are busy. When relay M is closed battery is connected with wires 19, 20 and 22, which wires are connected respectively to the primary, secondary and tertiary answering lamps A B and C,. It l ollows that the energization of relay M, causes all three answering lamps to light. The circuits for relays M and M, are similar to the circuits for relay M Itis clear from the above description of the circuit of relay M, that in the present modification the signal for anincoming call .is given by all three lamps in case all. three positions are busy. However, as soon as one of the positions becomes tree its relay 6,,

G, or G, becomes dcener -ized, so that its contact 4, 11 or 16 breaks the circuit for relay M, and closes the circuit for the corresponding primary, secondary or tertiary answering lamp, as the case may be. Thus this modification of the invention, as well as in the 1 revious one, the signal. disappears at a busy position remaining only at the position where the operator is free to answer the call.

Although on] two forms of the invention are shown and described. herein, it is understood that various changes and modifications may be made therein within the scope of. the following claims without departing from the spirit and scope or the invention.

lVh at is clmed is:

l. in a switchboard having a number of positions arranged in a designated order, the coinbinationv otmeans for indicating a call only at the first free position of said order with means for causing an indication of said call a predetermined position of said number when all the positions are busy.

2. 111 a switchboard having a number of positions arranged in a designated order, means for indicating call on the first :tree position of said order and means operating when all 'iositions oi the number are busy for causing a temporary indication of said call at the first position of the number until one of the positions becomes free.

3. In a switchboard having a number of positions arranged in a designated order, circuit for each position for causing an indication of call thereon, means for causing the circuit of the first free position of said order to respond to a call, and an electrical connection for the circuit of the first position operating when all oi. said positions are busy to cause a temporary indication of said call at the first position.

l. In a multiple telephone switchboard, an indication circuit comprising a plurality of branches, one for each of a plurality of positions, each branch comprising means for indicating an incoming call, means for each branch operative when the corresponding position isbusy for causing the indication current to flow in the succeeding branch and means for causing the cu rent to flow in a predetermined branch when all of said positions are busy.

5. In a multiple telephone switchboard, a circuit comprising a plurality of branches, one for each oiia plurality of positions,

means in each branch for indicating an incoming call, a normally closed contact in the first branch, a normally open and a normally closed contact in each succeeding branch, means for each position operative when said position is busy to open the nor mally closed contact of the corresponding branch and close the normally open contact of the succeeding branch, and means operative on opening of the normally closed contacts of all of said branches for causing an operationo'f the indicating means in a predetermined branch.

6. In a multiple telephone switchboard, a circuit comprising a plurality of branches, one for each of a plurality of positions, means in each branch for indicating an incoming call, a normally closed contact in the first branch, a normally open and a normally closed contact in each succeeding branch, means for each position operative when said position is busy to open the normally closed contact of the corresponding branch and close the normally open contact of the succeeding branch, an electrical'connection to a predetermined branch, and means operative on closure of all oi said normally open contacts to cause flow of current through said connection to said predetermined branch. i

7. Ina multiple telephone switchboard,

a circuit comprising a plurality of branches,

one for each of a plurality of positions, means in each branch for indicating an incoming call, a normally closed contact in the first branch, a normally open and a normally closed contact in each succeeding branch, means in each position operative when said position is busy to open the normally closed contact of the corresponding branch and close the normally open contactof the succeeding branch, and an electrical connection to the first branch to shunt the normally closed contact therein when all of said normally closed contacts are open,

8. In a multiple telephone switchbard, primary, secondary and teritary answering lamps for each position, means whereby an incoming call on any position is normally indicated by a primary answering lamp of said position, means operative when said position busy for causing said call to be indicated by a secondary answering lamp oi another position, means operative when both of the foregoing positions are busy for causing said call to be indicated by a teritary answering lamp of a third position and means operative when all three positions are busy to cause said call to be indicated by the first mentioned primary answering lamp.

9. In a switchboard, three positions, means for indicating a call at the first of said posit-ionswhen said position is free, means for indicating said call at the second position if the first position is busy and said second position is free, means for indicating said call at the third position ii: both the first and second positions are busy and the third tree, and means for indicating the call at the first position if all three are busy, said means being arranged to transfer the indication of said call to the second or third position in case either of said positions is first to become free.

10. In a multiple telephone switchboard, a device for indicating a call, means for preventing the functioning of said device when one position of the board is busy and means governed by the busy or free condition of another position oi the board for, at times, rendering said first mentioned means ineffective to prevent the functioning of said device.

11. In a multiple telephone switchboard, means for indicating an incoming call at one position of the board, a circuit for preventing the operation oisa-id meanswhen said position is busy, a second circuit for, at times, rendering said first mentioned circuit ineffective to prevent the operation of said means and means whereby said second circuit is governed by the busy or free condition of another position of the board.

12. In aswitchboard having a number of positions, the combination of means for indicating an incoming call only at the first free position of said number, with means for causing an indication of said call at a plurality of positions when all the positions of the number are busy.

13. In a switchboard having a number of positions, means for indicating a call on the first "free position of the number and means operating when all positions of the number are busy for causing a temporary indication of said call at all of the positions until one of the positions becomes free.-

1,427,ees I i i. In a switchboard having a number 01' positions, a circuit for each position for causing an indication of a call thereat,means for causing the circuit of the first free position 01? the number to respond to a call and electrical connections for the circuits of t ie said positions operating when all of said positions are busy to cause a temporary indication of said call on all of said positions.

15. In a multiple telephone switchboard, a circuit comprising a plurality or" branches, one or each of a plurality ct positions, means in each branch for indicating an incoming call, a normally closed contact in the first branch, a normally open and normally closed contact in each succeeding branch, means at each position operative when said position is busy to open the normally closed contact off a corresponding branch and close the normally open contact of the succeeding branch, and an electro magnetic translating device controlled by a contact in each branch for sending current through a predeteri'nined branch when all of said normally closed contacts open.

16. In a multiple telephone switchboard, a circuit comprising a plurality of branches, one for each of a plurality of positions, means in each branch for indicating an incoming call, a normally closed contact in the first branch, a normally open and a normally closed contact in each succeeding branch, means in each position operative when said position is busy to open the normally closed contact of a corresponding branch and close the normally open con tact of the succeeding branch, a normally open electrical connection to one of said branches, and an electromagnetic translating device for closing said connection when all of said normally closed contacts are open.

17. In a multiple telephone switchboard, a circuit comprising a plurality of branches, one for each of a plurality of positions, each branch comprising means for indicating an incoming call, a normally closed contact in the first branch, a normally open and a normally closed contact in each succeeding branch, means in each position operative when said position is busy to open the nor mally closedcontact of the corresponding branch and close the normally open contact of the succeeding branch, normally open electrical connections to all of said branches,

an electromagnetic translating device for closing said connections and means for en nrst and second positions are busy rd free, means for indicating the c it all of said positions if all three are i 1 .c iris-1 said means .oeing arranged to transier +1 1, n. ,1"- s H t +1 0 d lflplx, on or salt ca 0 no secon or thn pos case either of said posltions is in, to become free.

19. in a multiple telephone switchboard,

ary, secondary and tertiary answering e for each incoming call, said lamps '19; located different positions of the tchboard, means for ordinarily lighting be p "imary lamp in response to an ing ca l, means for lighting a secondary lamp at arothr position of the switchboard it the operator at the primary lamp is busy, for lighting only a tertiary lamp at still another position of the switchboard if the operators at both the primary and sec ondary lamps are bus"- and means for light 1' all or said lamps when the operators at all of said positions are busy.

20. in a multiple telephone switchboard, a device for indicating a call, means for preventing the functioning of said device when one position of the board is busy and means governed by the concurrent busy or singly board for, L imes, rendering said first men-- tioned means ineffective to prevent the func- ROBERT W. MORRIS.

" e condition of two other positions of the,

.ior indicating an incoming call at 

